Karl + Petra

Why Karl and Petra work together

A coded synergy (score 94): Petra's Blood Resonance names Karl, and Karl's Burst applies the HP Reduction debuff that turns her bonus on.

Karl's Fire & Brimstone (factor 12,500) cuts the target's HP by 25% for 2 seconds. Glory of War raises Berserker ATK by 20% and reflects part of the damage his shields absorb. Flame's Blessing shields his troop and an ally, and Backfire sets attackers Burning on counterattack. Awakened, he deals 15% more continuous damage to HP-Reduced targets.

Petra's Burst (factor 16,000, 17,000 awakened) also raises her counterattack damage for 5 seconds. Blood Resonance gives bonus damage to debuffed enemies, and the bonus triples when she is deployed with Karl (up to +30% damage and -10% damage taken for Berserkers). Iron Wall Formation adds Berserker HP and damage. Dual-Sided Command only works above 13.5M damage per second, so it rarely matters.

Key skills at max level

Karl

• Fire & Brimstone (Burst): Deals damage to the target and applies HP Reduction for 2 seconds.
• Glory of War (Passive): Increases ATK of Berserker soldiers, and turns part of the damage absorbed by shields back on the enemy.
• Flame's Blessing (Passive): Normal attacks have a 20% chance to shield Karl's troop and one allied troop for 2 seconds. Once every 6 seconds.

Petra

• Counterattack Overture (Burst): One-time strike that also raises her own counterattack damage for 5 seconds.
• Dual-Sided Command (Passive): Only when the troop deals over 13.5M damage per second: as commander, reduces damage of hit targets for 2 seconds; as lieutenant, grants one heal.
• Iron Wall Formation (Passive): Raises HP and damage of Berserker soldiers.

Skill upgrade order

Karl

1. Glory of War
2. Fire & Brimstone
3. Flame's Blessing
4. Backfire

Petra

1. Blood Resonance
2. Iron Wall Formation
3. Counterattack Overture
4. Dual-Sided Command

Talent build

Karl's talent trees: Berserker, Versatile, Defense. For Open field and PvP:

1. Max the Berserker tree first.
2. Then the Defense tree: Superior Defense (+1.6% DEF per star), Prevention Priorities (−10% skill damage taken) and Stockpiled Medicine.

See the open-field damage build and every talent node.

Troop mix

100% Berserkers.

Swaps if you don't have Petra

• Ganglot F2P: Skip
• Kalthas F2P: Invest

Questions players ask

Is Karl + Petra a good pairing?

Yes for open field and pvp. Karl's HP Reduction triples Petra's Blood Resonance.

Who should be commander, Karl or Petra?

Karl commands and Petra is lieutenant. Both heroes' skills apply, but some skills only work in one role; see the skills section on this page.

What troops should Karl and Petra lead?

100% Berserkers.